This deck is a variation of Kripp's Murloc Paladin that uses 2 Shieldbreaker instead of 2 Acolyte of Pain. Kripp said the deck can suffer from low card draw, but even with the 2 Acolytes, it suffers. Adding in the Shieldbreakers helps get rid of Bone Wraith and Khartut Defender. It also shuts down taunt warrior, and any mech with Zilliax, Annoy-o-Module, or Bronze Gatekeeper attached to it. Shieldbreaker also more often than not will open the enemy up for the final blow you need to secure the win.
MULLIGAN: When you're doing your mulligan with this deck I have a rule for myself since you wanna avoid drawing Tip the Scales. I limit the removal to 2 cards; this just seems to work the best seeing as how I rarely get Tip the Scales when I do this compared to when I don't. However, if you start with both Tip the Scales, feel free to Mulligan all cards if needed. Also, if you start with coin, try to coin into Prismatic Lens if possible.
The Murloc Warleader and Toxfin is so you can put early game pressure on the Mage since most of their Aoe spells are higher in mana. Do watch out and try to play around Flame Ward because it will waste you if you're not careful. And remember, Flame Ward only activates after you've done damage, so if you have to trigger it, hit them with your biggest minion.
The reason you'd keep Sir Finley of the Sands when you have a Prismatic Lens is so when you draw your Tip the Scales and play it, you're almost out of cards to get Sir Finley activated. And if you draw the 2nd Prismatic from the 1st you can always play the 2/3 Murloc.
This can still work if you don't have all/any legendaries, you can exchange any of them for any of these: